Cooper Bussmann GMD-3-R 3A Time Delay Cartridge Fuse

Product Description

The COOPER BUSSMANN GMD-3-R is a glass-body, cartridge-style time delay fuse rated at 3 amps. It measures 20 millimeters in overall length and 5 millimeters in diameter, placing it in the IEC 20x5 mm mini fuse form factor. The time delay characteristic allows brief inrush currents to pass without nuisance opening, making it suitable for protecting circuits where motors, capacitors, or transformers cause momentary surges at startup. Licensed electricians and electronics technicians install this fuse in control panels, instruments, and low-current branch circuits where precise overcurrent protection is required.

This fuse is intended for use in low-voltage control circuits, instrumentation, and light industrial equipment operating at up to 250 volts. The glass body allows visual inspection of the element without removal, simplifying diagnostic work during service calls. Its compact 20x5 mm form fits standard fuse holders and blocks designed for IEC-style mini cartridge fuses, common in HVAC control boards, laboratory instruments, and imported equipment requiring metric-format fuse components.

Key Features

• Time delay action tolerates startup inrush without nuisance trips
• Glass body allows visual fuse-element inspection in the field
• 10,000A interrupting rating at 125V for robust fault current handling
• 100A interrupting rating at 250V
• Meets UL, CSA, PSE/JET, and RoHS certification requirements
• Standard IEC 20x5 mm cartridge form fits common fuse holders

Compatibility

Designed as an OEM-style replacement for IEC 20x5 mm cartridge time delay fuse positions in control panels, instrumentation, and light industrial equipment.

Installation Notes

Installation should be performed by a qualified electrician in accordance with the National Electrical Code (NEC) and applicable local codes. De-energize and lock out the circuit before removing or installing any fuse. Verify that the replacement fuse amperage, voltage rating, and time-delay characteristics match the original equipment specification before inserting. Do not substitute a fast-acting fuse in an application designed for a time delay element, as nuisance opening or inadequate protection may result.